Sharpener for cutting machines



May 8, 1934. J. B. GURY SHARPENER FOR CUTTING MACHINES Filed May 15, 1930 ?atentecl May 8, 1934 eerie 7 Claims.

This invention relates to sharpeners for the blades of cutting machines.

An object of this invention is to provide improved mechanism for sharpening the blade of a cutting machine having a pair of spaced sharpening disks arranged to be self-centering whereby the inner edge of each disk will contact with an edge of the blade and thereby uniformly sharpen both sides of the blade at one operation.

Other objects will be apparent from the detail description taken in connection with the accompanying drawing, in which:

Fig. 1 is a plan view of a cutting machine with the sharpener.

Fig. 2 is a cross section on line 2-2, Fig. 1.

Fig. 3 is a vertical section on line 3-3, Fig. 2.

Fig. i is a vertical section on line 44, Fig. 2.

Fig. 5 is a detail perspective of the sharpener.

The embodiment illustrated in the drawing includes a cloth cutting machine having a rotary blade. The sharpening mechanism is supported on the frame of the machine by a bracket and includes a pair of abrasive disks mounted in spaced relationship on either side of the blade and upon a sleeve adapted for free rotary movement along a shaft carried by the bracket. By tilting the shaft, the inner surface of each of the disks is brought into contact with an edge of the cutting blade in such a manner as to uniformly grind each side of the blade. The construction and operation of the device may be clearly.

understood from the detail description which follows.

The cutting machine may include a base 1, a

' frame member 2 supporting a motor 3, and a rotary shaft 4 carrying a cutter blade 5. The arrangement is such that the shaft 4, and thereby the blade 5, is driven at a high speed by the motor 3.

It is to be understood, of course, that the details of construction of the machine itself are no part of this invention and need not, therefore, be specifically described.

The frame 2 has 2. lug 6 upon which a bracket 7 may be adjustably supported. Preferred means for supporting the bracket are shown in Fig. 2, in which a groove is provided in the face of the lug 6 adapted to receive the shank of the bracket 7. A slot 8 is provided in the shank of the bracket '7 through which may be inserted the point of a thumb screw 9. It will be apparent that by loosening the thumb screw 9 the bracket may be moved to and clamped in different positions.

As illustrated in the drawing the bracket has an arm 10 to which is secured a sleeve 11. A shaft 12 passes through the sleeve and is secured at its inner end to a yoke 13 which spans and supports a horizontal shaft 14 upon which the abrasive members may be mounted.

The abrasive elements comprise a pair of spaced abrasive disks 15 secured to a sleeve 16 in spaced relationship in order to provide between them an open path for the blade when the sharpener is not in use. A leaf spring 17 secured to the bracket 7 by a screw 18 is formed and positioned in such a way as to lie against the bottom surface of the yoke 13, and thus hold it with the shaft 14 normally in horizontal position and to return those members to a horizontal position after they have been tilted in order to sharpen the blade.

The means for tilting the shaft 14 and thereby the sharpening members 15 comprises a lever 19 secured by a set screw 20 to the outer end of the shaft 12. The lever 19 may have a lug 21 adapted for finger engagement and is shown in the drawing as positioned close to a handle 22 on the sharpener so that it may be conveniently manipulated by a finger while the hand engages the handle.

The distance of throw, or the angle of inclination of the shaft 14, may be regulated by means of an abutment plate 23 secured by a collar 24 to the sleeve 11 in cooperation with a distance screw 25 on the lever 19. The screw 25 is adjustable, operating through a boss 26 on the lever 19 and is provided with a detent spring 27.

The blade 5 will normally rotate free of the abrasive members, the edge rotating in a path between the abrasive disks 15. When it is desired to sharpen the blade a finger may engage the lug 21 thus tilting the yoke 13 and with it the shaft 14 and the abrasive members 15. By reason of the fact that the members 15 are carried by the sleeve 16, which is freely slidable in the shaft 14, the inner edges of the abrasive disks will come into uniform contact with the cutting edge of the blade.

The mounting for the abrasive disks 15 is preferably arranged so that the distance between the disks may be adjusted. This is accomplished in the embodiment shown in the drawing, see Fig. 3, by providing a collar 28 in threaded engagement with the sleeve 16 and securing one of the disks to the collar by a nut 29. The collar 28 may be held against displacement on the sleeve 16 by a set screw 30. By adjusting the distance between the disks bevels on the blade of dilferent acuteness may be ground. When the disks are close together the bevels on each side of the plate will meet each other at a very acute angle and the angle may be enlarged by increasing the space between the disks.

It will be apparent that the construction including the pair of spaced disks secured to a sleeve loosely mounted on a shaft permits the selfcentering of the sharpening elements so that the pressure of both disks against the blade is always equal. It also permits the adjustment of the disks to be made simple in that the adjustment of one disk only is necessary.

It is to be understood that parts of the invention may be used to advantage Without the whole, and that various changes may be made in the details of construction within the scope of the appended claims without departing from the spirit of this invention.

I claim:

1. In a device of the class described which has a frame and a cutter blade mounted on said frame, a sharpener including a shaft supported on the frame transverse of the plane of the blade, a sleeve mounted on the shaft for free rotary and endwise movement, a pair of spaced abrasive disks securedto said. sleeve, resilient means for normally retaining the shaft in a plane transverse of the blade, and means for tilting the shaft to bring the inner surfaces of both disks into contact simultaneously with the blade.

2. In a device of the class described which has a frame and a cutter blade mounted on said frame, a sharpener including a bracket mounted on the frame and pivotally supporting a yoke, a shaft carried by the yoke, a pair of abrasive disks spaced from each other in fixed relationship and mounted for free rotary and endwise movement on the shaft and in such a manner as to provide a path for the blade between the disks during normal operation of the cutter blade, and means for adjusting said bracket to vary the distance of the shaft from the edge of the blade.

3. In a device of the class described which has a frame and a cutter blade mounted on said frame, a sharpener including a bracket mounted on the frame pivotally supporting a yoke, a shaft carried by the yoke, a pair of abrasive disks spaced from each other in spaced relationship and mounted for free rotary and endwise movement on the shaft, and means L07: tilting the shaft.

4. In a device of the class described which has a frame and a cutter blade mounted on said frame, a sharpener including a shaft supported on the frame transverse of the plane of the blade, a sleeve mounted on the shaft for free rotary and endwise movement, a pair of spaced abrasive disks secured to said sleeve, means for tilting the shaft, and an adjustable stop to limit the angle of inclination.

5. In a device of the class described which has a frame and a cutter blade mounted on said frame, a sharpener including a bracket adjustably supported by the frame, a yoke pivotally supported on the bracket, a shaft carried by the yoke, a sleeve mounted on the shaft for free rotary and endwise movement, a pair of spaced abrasive disks secured to said sleeve, resilient means cooperating with the yoke to hold the shaft normally in a plane perpendicular to the blade, and manual engaging means on the yoke for inclining the shaft out of perpendicular.

6. In a machine of the character described having a frame and a rotary cutter blade mounted therein; a yoke supported for turning movements, a shaft supported by said yoke approximately parallel with the axis of said cutter blade, a pair of abrasive disks supported by said shaft for free endwise and rotary movements, means for holding said disks in definitely spaced relationship from each other, means for turning said yoke to incline said shaft and thereby the axis of said disks with respect to the axis of said blade and to engage said disks simultaneously with opposite sides of the marginal portion of said blade, and means for turning said yoke to its initial position to disengage said disks from said blade.

'7. In a machine of the character described having a frame and a rotary cutter blade supported thereby; a sharpener including a shaft supported on said frame normally parallel to the axis of the blade, a sleeve mounted on the shaft for free rotary and endwise movements, a pair of disks secured to said sleeve and separated by an intervening space into which the marginal portion of said blade extends, means for tilting said shaft to bring said disks simultaneously into engagement with opposite sides of the mar ginal portion of said blade, and a spring for returning the shaft to and holding the same in normal position in which said disks are out of engagement with said blade.

JOHN B. GURY. 

